package com.cms.web;

/**
 * <p>Title: ECM</p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: </p>
 * @author Anthony Han
 * @version 4.0
 */

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import org.apache.log4j.Logger;

public class SetCharacterEncodingFilter implements Filter {

	private final static Logger logger = Logger
			.getLogger(SetCharacterEncodingFilter.class);

	protected String encoding = null;
	protected FilterConfig filterConfig = null;
	protected boolean ignore = true;

	/** * Take this filter out of service. */
	public void destroy() {
		this.encoding = null;
		this.filterConfig = null;
	}

	/**
	 * * Select and set (if specified) the character encoding to be used to *
	 * interpret request parameters for this request.
	 */

	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		// Conditionally select and set the character encoding to be used

		if (ignore || (request.getCharacterEncoding() == null)) {
			String encoding = selectEncoding(request);
			if (encoding != null) {
				request.setCharacterEncoding(encoding);
				response.setContentType("text/html; charset=" + encoding);
			}
		}

		// logger.debug(request.getCharacterEncoding());

		// Pass control on to the next filter
		chain.doFilter(request, response);

	}

	/** * Place this filter into service. */
	public void init(FilterConfig filterConfig) throws ServletException {
		this.filterConfig = filterConfig;
		this.encoding = filterConfig.getInitParameter("encoding");
		String value = filterConfig.getInitParameter("ignore");
		if (value == null) {
			this.ignore = true;
		} else if (value.equalsIgnoreCase("true")) {
			this.ignore = true;
		} else if (value.equalsIgnoreCase("yes")) {
			this.ignore = true;
		} else {
			this.ignore = false;
		}
	}

	/**
	 * * Select an appropriate character encoding to be used, based on the *
	 * characteristics of the current request and/or filter initialization *
	 * parameters. If no character encoding should be set, return * null.
	 */
	protected String selectEncoding(ServletRequest request) {
		return (this.encoding);

	}
}
